'use strict';
const PluginError = require('plugin-error');
const htmlmin = require('html-minifier');
const through2 = require('through2');

module.exports = options => {
    return through2.obj(function(file, enc, next) {
        if (file.isNull()) {
            next(null, file);
            return;
        }

        const minify = (buf, _, cb) => {
            try {
                let contents = Buffer.from(htmlmin.minify(buf.toString(), options));
                if (next === cb) {
                    file.contents = contents;
                    cb(null, file);
                    return;
                }
                cb(null, contents);
                next(null, file);
            } catch (err) {
                let opts = Object.assign({}, options, { fileName: file.path });
                let error = new PluginError('gulp-htmlmin', err, opts);
                if (next !== cb) {
                    next(error);
                    return;
                }
                cb(error);
            }
        };

        if (file.isStream()) {
            file.contents = file.contents.pipe(through2(minify));
        } else {
            minify(file.contents, null, next);
        }
    });
};
